I created a widget from twitter.com and “embed” and pasted the code. I get this message on my first trial website I’ve created:
This script will only appear on the published/exported site.
Does this mean I can’t see what it will look like (on all devices) until I publish?
Yes, webflow doesnt complie the data until you press publish and then view the site.
Surely a few minutes of funny font colours wont hurt while you iron it out?
Unless you make a secret button in your footer that opens a new zone with the code hidden inside… that way your users have a very small change of stumbling across it 
Ok - thanks for that.